Pipe fitting is necessary in many different trades, including, but not limited to plumbing, HVAC, refrigeration, manufacturing, fire prevention, and many others. Among the most widely used metal pipe is copper tubing, which is favored for its abundance, ductility and high resistance to corrosion, Copper tubing is most often used for supply of hot and cold water, and as a refrigerant line in HVAC and refrigeration systems. Copper tubing is typically joined using a flare connection, compression connection, crimp fitting, sweat (i.e., solder) or swedge.
Flare connections require that the end of a tubing section be spread outward in a bell shape using a flare tool. A flare nut then compresses this bell-shaped end onto a male fitting. Flare connections are labor intensive but are quite reliable over the course of many years.
Sweat fittings are smooth couplings that easily slip onto the end of a tubing section. The joint is then heated using a torch, and solder is melted into the connection. When the solder cools, it forms a very strong bond.
Compression fittings use a soft metal ring (i.e., a compression ring) which is squeezed onto the pipe and into the fitting by a compression nut. The soft metal ring conforms to the surface of the tubing and the fitting, and creates a seal. Compression connections are time consuming to make and sometimes require retightening over time to stop leaks.
Crimped or pressed connections use special copper fittings which are permanently attached to rigid copper tubing with a powered crimper. The fittings, manufactured with sealant already inside, slide over the tubing to be connected. Substantial pressure is exerted to deform the fitting and compress the sealant against the inner copper tubing, creating a water tight seal.
Swedging is a metal-forming technique in which a receiving end of a tube is precisely expanded using a die. The mating end of another tube is inserted into the expanded end. The joint is then heated using a torch, and solder is melted into the connection. When the solder cools, it forms a very strong bond.
There are many examples of swedging tools known in the prior art. For example, U.S. Pat. No. 2,679,681 to Resler discloses a swedging method. After thinning (i.e., counterboring) the wall of the end of a length of tubing by drilling, the tubing is firmly held by clamping as a punch is urged into the counterbored section. Not only is counterboring time consuming, but it is imprecise and conducive to uneven thinning or damaging of the wall. Also, Resler provides no means to facilitate rapid and repeatable urging of the punch into the thinned wall section.
As another example, U.S. Pat. No. 3,380,285 to Wilson discloses an assembly of nested swedging tools of various sizes for covering a wide range of tubing diameters. To expand a pipe, a chosen swedging tool is driven by hammer blows. The tool requires manual strikes which tend to be inconsistent, off-centered and tedious, especially for a professional who may have to join many tubing sections in a work day.
As yet another example, U.S. Pat. No. 5,046,349 to Velte discloses a lever-actuated expander with means to grip a pipe and urge a conical mandrel into the open end of the pipe for expansion. Actuation is limited by the manual gripping force of a user. Setting the tube up for use is tedious. Slippage results in an imperfect flaring.
What is needed is an easy to use, consistently reliable, powered tool for swedging or flaring the end of tubing for joining to like tubing. The tool should be configured to work with existing air or electric powered impact equipment. The invention is directed to overcoming one or more of the problems and solving one or more of the needs as set forth above.